Titanium alloy having excellent high-temperature oxidation and corrosion resistance

Abstract

A titanium alloy having excellent high-temperature oxidation and corrosion resistance is disclosed which comprises, by mass, Al: 0.30–1.50%, and Si: 0.10–1.0%. Preferably, amass ratio Si/Al is not less than 1/3. More preferably, the titanium alloy further comprises Nb: 0.1–0.5% by mass. The titanium alloy is useful as an exhaust system material for a vehicle or a motorbike, which enhances corrosion and high-temperature oxidation resistance, while utilizing inherent lightness and corrosion resistance of an original titanium alloy without impairing economy and workability.

1. An exhaust system made of a titanium alloy comprising, by mass, Al: 0.30–1.50%, and Si: 0.10–1.0%, wherein amass ratio Si/Al is not less than 1/3. 
     
     
       2. The exhaust system according to  claim 1 , wherein the mass ratio Si/Al is not more than 1.5. 
     
     
       3. The exhaust system according to  claim 1 , further comprising Nb: 0.1–0.5% by mass. 
     
     
       4. The exhaust system according to  claim 1 , further comprising at least one additional element selected from the group consisting of Ta, W, Mo, Cr, Zr and Hf, wherein a total amount of the Al, the Si and the at least one additional element is not more than 2.5% by mass. 
     
     
       5. The exhaust system according to  claim 1 , wherein the alloy has a surface thereof subjected to aluminum-based plating. 
     
     
       6. The exhaust system according to  claim 5 , wherein a thickness of the aluminum-based plating is 1 μm or more. 
     
     
       7. The exhaust system according to  claim 1 , wherein the exhaust system is a muffler.